Method of applying heads to stems



March 3, 1931. M. J. BoYLE 1,794,942

METHOD 0F APPLYING HEADS TO STEMS Filed oct. 51, 1927 i E3. m i ww r yivA9 1 gt s/ 5% Patented Mar. 3, 1931 UNITED STATES MICHAEL J. BoYLE, orCHICAGO, ILLINOIS METHOD or AIILYIIIGf HEADS To sTEMs Application ledOctober 31.,` 1927. ".Serial No.v 229,984.`

This invention relates to the applying of heads or the like to stems orrods and is par ticularly applicable tothe forming of valves, tappets,or other similar articles. It has been proposed to form or secure headsof one kind of metal, such, for instance, as best adapted for formingvalves, and the stems of another' kind of metal best adapted for thispurpose, but such efforts have heretofore proven more or lessunsuccessful on account of the diiiiculty of properly forming the end ofthe stem and the valve or head and welding them together so that thehead will not become loose. In accordance with the present method, Iproduce valves ortappets with the heads securely welded to the stems sothat they are practically inseparable.

In the accompanying drawings:

Figure 1 is a sectional View of the forming device used for forming theheading operation; and

Figure 2 isa similar view showing the position of the parts at the endof the stroke or finishing operation.

In accordance with this invention, I provide a stem 3 which may beeither solid, as shown, or of hollow or tubular construction, and abillet t from which the head is to be formed.A The billet isprovidedwith a hole 5 for receiving the end of the stem, as shown inFigure 1. When the head is to be applied to the stem, they are iirstheated to a suili ciently high temperature to permit the welding of thehead to the stem during the forming process, which will presently bedescribed. In this connection, it will be noted that when the heads andstems are made of the metals now found to be most suitable for theseparts for `valves, the temperature to which they are heated is greatlyin excess of the ordinary temperatures used in connection with formingoperations. The stem with the billet applied thereto is inserted in adie 6 mounted in a die fixture body 7 having a central longitudinalopening 8 in which are placed valve stem guides 9, these beingvchangeable for dierent sized stems. The lower end of the stem alsopreferably engages with a stem supporting pin 10 which is alsochangeableAfor stems of different sizes i or lengths. The lower end of the stem 3or supporting pinlO, as the case may be,'en gages with a plunger 11mounted in the lower end ofthe body or die support 7. The-lower endofthe body is threaded, as shown at l2 for receivinga reduced end 15 ofthe plunger 11, the arrangement being such that the shoulder 16 willengage with the cap to limit the movementof the plunger. A spring 17 isinterposed between the cap and an annular shoulder 18 on the plunger andtends to hold the plunger in raised position. The use of such springpressed plunger forms one of the principal novel features of thisinvention and springs of the proper size or'strength must be carefullyselected forruse in the manufae ture of different sized valves, tappetsor the like in order to produce the desired results.

' The upper forming die 19,' which cooperates with the lower die andwith the spring pressed plunger in the forming operation, is

securedin the diexturebody or holder 2O in the usual manner, itbeingunderstood that these dies are actuated by any ordinary or preferredform of press. IVhen the die 19 moves downwardly or toward the die 6 thebillet 4 is pressed or forged to the desired shapein accordance with theform of the dies and the upper end of the stem 3 is mushroomed out orexpanded to form a head 21 which consists mainly in a thin annular finor disk tapering to a sharp edge, this headed portion of the stemfitting within a similarly shaped recess in the head 22 which is formedfrom the billet 4 and being welded thereto throughout more or less ofits area, such welding usually being around the 1in-like disk only.During this forming and welding action the stem and billet movedownwardly against the pressure of the spring 17 or until the lower endof the plunger 11 strikes the cap 13. The length of this movement may beadjusted by adjusting the cap, and if desired, the tension on the springmay also be adjusted in this manner. I have found that this yieldingsupport for the stem and billet causes a much more uniform forming andwelding operation and that the articles comf` pleted in this manner aremuch more uniform than when the stem and billet are supported rigidly orin the usual manner. l o

As above suggested, my invention is applicable to forming variousarticles and may be p utilized for various purposes; therefore I do notWishto .be .limited to .the exact method v or apparatus herein.;shown.and described, 'exe cept as speciiied in the following claimsnln i 10which I claim:

1. The method of forming headed articles f which consists in applying abillet to one end of the stem heating the same, then subjecting thebillet and stem While in heated condi- Y Y'15 tion to the action offorming diesto forln the desired head,` said stem .being resilientlysup- -pOl-.tedduring a portion ofthe forming action .andi-rigidlysupported during the remainder ofthe forming action;

f2-0 I, 2. Afllhie hereinjdeseribed method articles `Which consists .inproviding ahead forniingf` meinberwith a hole therein, fthenin- Isertingafstenn in thehole, then subjecting the p head formi-ng member andladjacent portion f O thestem While in highly yheated condition `tol-theaction offorming dies, the stern being resiliently'supportedduring'a portion of such 'orming action to resist `the raction 'of one of .thedies, )and Y held v in J{ixed position during the remainder ,o2-lf fsuch'forming action the l.

operation .beingsuch that when the head is formed, the .upper end :of.thefstem will simulftaneously be spread Ito form V.a ,sharp ledgeddisk-like portionwhich is Weldedto the head.y

, kA forgingaandjweldingmethod orunit- 'fing' a -head and stem, whichconsists 'in insert- Ving the stem in :a hole-in abil-let and heatingt'the billet :and adjacent portion .of the stein `toa highWeldingtemperatu-re, vvthen subjecto @ingthe billetland-stemwhile/,heatedfto the ao ation of form-ing diesfduring which action, thefsteni isyresiliently(supported vduring 4,a portion ofthe-time,andzrigidly supported during the remainder of the'ltime.

4:5 n MICHAEL J. noir-*Lny

